In the logistics sector, tonnage can be described, in its simplest definition, as cargo carrying capacity. The fact that the cargo carrying capacity of each vehicle is different leads to the need for different tonnage calculations. At the same time, an unsuitable cargo capacity for the vehicle can cause you to face some penalties, as well as lead to dangerous consequences.
These penalties can multiply the financial damage by causing you to be in a difficult position financially and resulting in damage to the vehicle. Therefore, tonnage is an important factor in terms of both safety and cost. Now, let's take a closer look at the definition of tonnage and how it should be calculated! ⏬
What is Tonnage?
Tonnage measures the amount of cargo a vehicle can carry in tons. Looking at the definition of tonnage for modern shipping; it can be described as the calculation of a ship's volume or cargo volume.
Tonnage is used to measure different cargo limits of vehicles of various sizes. While it is not used in a mechanical vehicle such as a tractor, it is used in large vehicles such as trucks or semi-trucks. ✅
How is Tonnage Calculated?
Some data is required for tonnage calculation. One of this information is the maximum laden weight specified in the registration document. Others are details regarding the dimensions of the vehicle.
Since all this data varies for each vehicle, the resulting tonnage measurement will also be different. You can obtain detailed information by browsing the different calculation types found in the rest of our article. 👇
Gross tonnage (GT) calculation
Gross tonnage is the measurement of the volume of all enclosed spaces of the ship. The asymmetrical shape of ships can make it difficult to determine the actual gross tonnage value. An estimable gross tonnage calculation is as follows: ⬇️
• K1 x V (K1 = 0.2 + 0.02LogV and V is the number of enclosed spaces in cubic meters)
Net tonnage (NT) calculation
Net tonnage can be defined as the molded volume of all cargo spaces of the ship. The ratio of net tonnage to gross tonnage is generally expected to be 30% less. In addition, net tonnage should be 90% of gross tonnage for sailing boats and 80% of gross tonnage for motorboats. Its calculation is as follows:
• K2 x Vc (4d/3D) ^2 + k3 x (N1+N2/10)
DWT (Deadweight Tonnage) calculation
DWT tonnage, referred to as deadweight, calculates the weight a ship can safely carry. The higher the DWT tonnage, the more active orders and customer demands can be resolved positively.
In making this calculation, the entire contents of the ship are taken into account. The following items can be given as examples: 👇
• Cargo capacity of the ship
• Cargo on board
• Provisions
• Fuel
• Weight of passengers and crew
Tonnage Calculations in Various Transport Modes (Road, Air, Sea, Rail)
The transport sector includes various transport modes: road, air, sea, and rail. It uses different tonnage calculation methods to determine the capacity of each transport mode. 👈
In road transport, heavy vehicles such as trucks and semi-trucks are generally used. In this transport mode, tonnage is based on the gross weight, which is the maximum amount of load the transport vehicle can carry.
Air transport, on the other hand, is weight-based, and the cargo capacity of aircraft depends on the total amount of cargo they can carry. The carrying capacity of aircraft is usually expressed in kilograms.
In maritime transport, the carrying capacity of ships is based on the "deadweight" (DWT) measure expressed in tons. DWT represents the maximum weight of cargo, fuel, fresh water, crew, and passengers that a ship can carry.
In rail transport, the carrying capacity of wagons is expressed in kilograms or tons, and there is a specific maximum load weight for each wagon.
Tonnage Calculation Examples
Tonnage is a calculation of great importance in the logistics sector that must be complied with. The tonnage calculation of each transport vehicle in this sector is different from one another. Some examples are included in the rest of the text. 👇
Tonnage calculation examples in container transport
If we take a 20-foot open top container as an example; ⬇️⏬
• Width: 2.35m
• Height: 2.35m
• Length: 5.89m
• Volume: 33m³
• Tare weight: 2400kg
• Payload capacity: 21,600kg
Tonnage calculation examples in road transport
In road transport, calculations are made based on carrying capacity (ton) and volume capacity (cubic meter). The tonnage capacity of a truck is determined by the gross weight specified in the technical specifications of the truck.
As an example, let's assume a truck has a carrying capacity of 10 tons and a volume capacity of 40 cubic meters in its technical specifications. If the total weight of the goods you want to load is 8 tons and the volume is 45 cubic meters, even though the tonnage capacity is sufficient here, this truck cannot carry the goods because the volume capacity is insufficient.
If the total weight of the goods you want to load is 12 tons and the volume is 35 cubic meters, even though the volume capacity is sufficient in this case, this truck cannot carry the goods because the tonnage capacity is insufficient.
Therefore, when making tonnage calculations in road transport, attention must be paid to both the total weight (tons) and the total volume (cubic meters) of the goods. The carrying and volume capacity of the truck must accommodate the total weight and volume of the goods.
Tonnage calculation examples in air cargo transport
Tonnage calculations in air cargo transport are generally based on the actual weight and volume of the products. The total weight a cargo aircraft can carry depends on the maximum takeoff weight of the aircraft, including fuel, crew, and cargo.
As a calculation example, let's consider an air cargo shipment. Let's say a package has an actual weight of 150 kilograms and a volume of 1 cubic meter (1m x 1m x 1m). However, in air transport calculations, the higher value between weight and volume is taken. The volumetric weight formula generally used in air cargo transport is:
Volumetric Weight (kg) = Length (cm) x Width (cm) x Height (cm) / 6000
For example, in this case, if the dimensions of the package are 100cm x 100cm x 100cm, it will be 166.67 kg using the volumetric weight calculation formula (1,000,000 / 6000). In this case, since the actual weight of the package is 150 kg, the tonnage calculation in air cargo transport is made over the volumetric weight. This is because the volumetric weight is greater than the actual weight.
Volumetric weight is particularly important in cargo transport because the carrying capacity of aircraft depends not only on weight but also on volume. A light but bulky load can occupy a significant area in the aircraft's cargo hold, which can prevent the carriage of heavier but less bulky loads. That is why volumetric weight is taken into account in tonnage calculations in air transport.
Tonnage calculation examples in ship transport
Gross tonnage, net tonnage, DWT tonnage, displacement tonnage, and light ship weight tonnage are used for ship transport tonnage calculation. To give an example: ⏬
• For a boat with a simple sailboat hull: Gross Tonnage = (.5 x L x B x D) divided by 100.
• For a sailboat with a keel: Gross Tonnage = (.375 x L x B x D) divided by 100.
• For speedboats: Gross Tonnage = (.67 x L x B x D) divided by 100.
Tonnage Calculation Tools and Formulas
You can access tonnage calculation tools online. You can calculate tonnage and obtain information by entering some details regarding your vehicle into these calculation tools.
The formula generally used for tonnage calculation can be described as "3.75 of the vehicle's maximum laden weight + the vehicle's maximum laden weight + 500 kg." At the same time, you can access the load amounts that generally apply to your vehicle type online to find out about your vehicle's tonnage limit.
Frequently Asked Questions
What are the common mistakes made in tonnage calculations and how can they be prevented?
The tonnage calculation process requires correctly understanding and using units of measurement, formulas, volume, and weight. Mixing different units or incorrect conversions can lead to misleading results. Likewise, using a wrong formula can lead to incorrect results in tonnage calculations.
During these operations, it is important to know which formula should be used according to the type of transport and the type of cargo. Furthermore, making measurements accurately is critical for the accuracy of the result.
One of the issues that causes the most confusion during the tonnage calculation process is not understanding the difference between volume and weight. These two concepts have different characteristics and cannot be directly interchanged. For an accurate tonnage calculation, it is necessary to understand the difference between volume and weight and to use these two concepts correctly. ✅
To achieve a more accurate and effective tonnage calculation, seeking help from a logistics or transport expert when necessary can also be highly beneficial. In this way, by avoiding misleading results, the transportation process can be made more efficient. 😍🔛
What is the impact of carrying capacity on costs?
Determining the tonnage carrying capacity prevents many negative situations. Various fines can be issued if limits are exceeded. Carrying more cargo than a vehicle is meant to carry can damage the vehicle's mechanism and environment. You can perform tonnage calculations to prevent this situation which directly affects your costs.
What are the factors to consider in tonnage calculations?
The tonnage calculation process plays a vital role in transport activities, and a range of factors must be considered. First of all, it is very important to be aware of the type of cargo. Because this determines the tonnage calculation formula to be used.
Furthermore, it is essential to accurately measure both the volume and the weight of the load. Volume and weight are the main components of tonnage calculation, and ensuring both measurements are carried out accurately guarantees an accurate result.
You must also consider what the mode of transport is. Tonnage calculations differ for road, sea, air, and rail transport. 👈
Conclusion
The evolving logistics across the world, when carried out with the correct practices, lead to efficient results in many ways. It is essential to master tonnage calculation in logistics for safe and suitable transport.
Thanks to accurate tonnage calculations, goals are met without damaging the vehicles and the environment. It is foreseen that incorrectly calculated tonnage can cause great financial damage to companies.
In this process, having detailed information about tonnage in logistics is the protagonist of making a significant step forward in optimization. By possessing knowledge about tonnage in logistics, you can put the most accurate transport operations into practice.
